On the afternoon of the 23rd, after exiting the Namyongin (Wonsam) IC on the Sejong–Pocheon Expressway, the landscape changed dramatically. As soon as we entered the national highway, a procession of dump trucks stretched endlessly, and construction vehicles shuttled nonstop between the large trucks kicking up dust. Wonsam-myeon in Cheoin-gu, Yongin, Gyeonggi Province, once a quiet farming village, was transforming into a massive semiconductor city.
This is where the Yongin Semiconductor Cluster General Industrial Complex that SK hynix is developing will be built. The total area is 4,153,502 square meters (about 1.26 million pyeong). It is 1.5 times the size of Yeouido and about the size of 600 soccer fields. As a single industrial complex, it is the largest in Korea. The site will house four semiconductor production facilities (fabs), a central utility building (CUB), wastewater and reclaimed-water treatment facilities, and other support infrastructure.
◇ Korea's largest construction site, the size of 600 soccer fields… 17,000 people deployed per day
The work is proceeding in two main sections. In the area for the first fab, the CUB, and the reclaimed-water treatment facility, building frame work was in full swing. On the site where fabs two through four will go, civil engineering continued, cutting into the hills and compacting the ground.
It was still hard to call the site a "road." Most roads were unpaved, and we had to go up and down bumpy hills. It was not easy to access without a four-wheel-drive vehicle. The dump truck tires going to and from the site were as tall as a person. With Caterpillar's off-road equipment, the payload is about twice that of regular vehicles, and the ability to drive on slopes is also superior.
On average, more than 17,000 people come and go from the site each day. There are about 200 water-spray trucks mobilized to reduce fugitive dust. The entire site resembled one giant "construction city."
The first fab, going up at the northernmost end of the complex, is under construction with completion targeted for Feb. next year. The exact progress rate has not been disclosed, but the adjacent CUB facility had already taken shape.
The first fab is about 150 meters tall, equivalent to a 50-story apartment building. Because semiconductor production lines are sensitive even to minute vibrations, the building foundation must go down 45 meters underground. To that end, tens of thousands of piles have been driven.
The structure is also unprecedented. The first fab will have six clean rooms, and the building is designed with a "triple mezzanine" structure. By placing two clean rooms on a single level to maximize space efficiency, the industry views it as the world's first attempt.
◇ With a higher floor area ratio, building the world's first triple-mezzanine fab
Regulatory easing is behind the ultra-large design. When Yongin City raised the floor area ratio from 350% to 490%, SK hynix, which had initially considered a double mezzanine, was able to apply a triple-mezzanine design. As a result, the total investment scale expanded from the initial 122 trillion won to as much as 600 trillion won. To that end, then-Yongin Mayor Lee Sang-il (now a preliminary candidate for Yongin mayor) was said to have visited the construction site once or twice every two months.
Administrative support also picked up speed. Yongin City approved "partial completion" for some sections of the industrial complex. Sections where infrastructure was first put in place were processed for completion so corporations could proceed with ownership registration and financing. It is seen as having eased investment schedules that had been blocked by concerns over project delays.
Full support from SK Group also followed. Inside the onsite PR center hung a handwritten message from SK Group Chairman Chey Tae-won. Visiting the site in Sept. 2023, Chey wrote, "I wish for the success of the Yongin semiconductor project, which is writing a new tradition and history of challenge and innovation."
Yongin City is also accelerating efforts to attract semiconductor materials, parts, and equipment companies, with Samsung Electronics national industrial complex (Idong and Namsa-eup) and SK hynix general industrial complex as the two pillars. Including the Korean subsidiaries of global equipment companies such as ASML, Lam Research, and Tokyo Electron, 93 corporations at home and abroad have moved in or are pursuing a move.
◇ Laying power, water, and roads… Wonsam-myeon is turning into a "semiconductor city"
Infrastructure expansion is proceeding in parallel. The substation that will supply power through a roughly 6-kilometer tunnel-type power duct from the Shin Anseong substation has mostly finished exterior work. Industrial water will be supplied from the Namhan River 37 kilometers away, and residential water from the Yurim reservoir 15 kilometers away.
The transportation network is also improving quickly. It takes 10 minutes by car from the plant to the Namyongin IC and 30 minutes to the Gangdong IC in Seoul. Via Yongin JC to the Yeongdong Expressway, it is also a 40-minute drive to SK hynix's plant in Icheon.
Efforts to coexist with the local community are continuing. SK hynix installed a free car wash for residents to prepare for construction dust and is creating a park along a nearby stream. Two zelkova trees on the construction site were also transplanted elsewhere at residents' request.